First we will take about some characteristics of the LED’s ,and put forward some require for LED power supply according to characteristics of LED. then description of work way with low power.
LED feature and drive power Requirements.
LED characteristics are as follows.LED is a PN junction device, with unidirectional conductivity, so it’s necessary to use a DC power supply or single pulse voltage. The forward voltage up to the start threshold after a current flowing through the LED.
To emit light, the LED light that are relative to this Current intensity.big current, current intensity; small, weak light, so LED must be supply power with constant current source. And voltage should be exceed in LED start voltage. And the LED characteristic is non-linear. As long as the forward voltage has little change. which Forward current changes will be large. The forward voltage and emit light color relative to the material of LED.RED GREEN and YELLOW led forward voltage drop is 1 .4～2．6V， white led forward voltage drop is large, for 3～4 .5v。when the forward current has been charged, the color of the emitted light will be offset, i.e., the color shift occurs. White led forward voltage Relationship with and white led forward current.Forward current
1、LED is non-line components for temperature sensitive. Temperature increases, the forward voltage drop is decreases. since the LED V-A characteristics is non-line, forward voltage drop has a little changed, then forward current will be changed is large. So must be using the constant current to supply power. or limiting current. Otherwise If using constant voltage to supply power. along with the temperature is increases. The forward voltage is decreases. The current is big and big, until it burned. Even the Devices in the same batch of production. High transparency plastic LED light strip includeing its forward voltage drop there will be some spectral rays. along with the temperature changed ,times flow ,equipment aging. So the driver circuit has feedback circuit is best. It can adjust of LED luminous color and intensity for real-time.

2、in order to highlight the effect of energy saving in LED,power conversion efficiency must be high, the demand of LED driver power can be attributed to the following.

3、Power supply must be DC voltage. further voltage is big than LED forward voltage.

4、requirement of power supply provide a current of constant and matching, to make a stable light and Brightness output.with power chang rate high,in order highlight the advantage of save-energy in LED.

5、in general, requirement of led has dimming function, so the driver power must be can adjust current. In order to carry out about the LED brightness, color and tone can be adjusted within a certain range.

6、has some protect function, such as open circuit protect,overvoltage protective and undervoltage lockout, and other functions.The original power supply LED The original power supply LED a lot supply by battery or AC power. such as batter supply power,in general the device of LED using rechargeable battery. Battery rang as 5～24v. rechargeable Battery has Rechargeable batteries are nickel batteries, nickel hydrogen batteries, lithium ion batteries.

1、nickel batteries
The first nickel battery was applied to mobile phone, its energy density is low, the volume is too big, capacity is too small,with more seriousis The memory effect of Ni MH battery, now has been replaced by the nickel hydrogen battery.

2、Nickel chloride (Ni – MH) battery Nickel battery are an environmentally friendly battery, rated voltage as 1 2v，energy density than nickel-chromium,battery has greatly improved.charge and discharge times of up to thousand times.price is very moderate.but the capacity is small than lithium-ion battery capacity。The advantages of lithiumion batteries is the higher the voltage of single cell, rated voltage of 3.6 ~ 3.7V. fully charged When the voltage is 4.2 ~ 4.4V, high energy density,small size:long cycle life, charge and discharge time Up to 500 ~ 1100 times: no memory effect;low self discharge rate,the monthly self discharge rate is 3% ~ 9% (nickel cadmiumElectricity is 25% ~ 30 ‰ Ni MH battery is 30% ~ 35%).Powered by batteries, in addition to bttery supply, also needs to use the DC, AC converter provides a constant current for LED, LED can also be composed of AC power supply, the need for a Ac to Dc converter,the first rectifier, filter,Then the cascade Dc, Dc buck converter, buck for LED power supply. Dc to Dc buck converter for switchType, it provides current to match the DC voltage and the constant and LED load.

LED street lamp remote control system (energy saving control, LED dimming, line alarm) – Modernization of street lighting system best management plan INTRODUCTION City street lighting is essential for people’s daily life in public facilities. Street lighting electricity consumption accounts for about 15% of total electricity consumption, all over the country to face the problems caused by power shortage and tight supply situation, street patrol is one work requires a lot of manpower for the municipal departments. A variety of temporary emergency energy-saving measures that are widely used: Night interval lights, street lights switch adjustment time .in power shortage days to turn off landscape lighting, etc., when after the peak, these measures may be put it away unheeded, next year’s peak season, everything will start again. Electricity saving measures the relief of the power shortage, meanwhile waste of resources has brought negative effects on people’s daily lives.Power shortage in the best and effective way is implementation of intelligent power management, reduce waste and make our every unit of electricity can turn material resources to good account! Enable advanced street light control system, can implementation of synchronization power management for city road lights. to ensure the night street lighting systems is efficient and stable with real-time monitoring and management.all day operation, effectively save energy consumption . For city public lighting systems, using intelligent management system is to achieve energy savings, reduce waste of resources to meet the demands of people’s lives, showing a modern city beautiful scenery scientific solutions.
System features:
1、Cost savings: installation is simple and quick, without laying lines; each box changes only need a GPRS transceiver, saving GPRS traffic. Use of existing power line communication control network, on the one hand to save the human and material resources;other hand wired communication is not affected by the weather and terrain Influence, also ensure the reliability of communication.
2, can be automatically power-off operation for every day; can ensure the power-off operation base on different time in holiday. Can be enable the electrical equipment partition , sub-line management.

Design Analysis and examples of high-power LED constant current drive circuit LM2734 is a 1A buck regulator. Based on constant current drive circuit LM2734 (Figure 3) using the LM321 op amp to obtain the sampling voltage resistance on the Rset, in combination with other resistors and capacitors can form a complete, high-efficiency power LED constant current drive circuit. In actual use, some LED constant current drive circuit can be directly obtained feedback voltage from the sampling resistor, as shown in figure 4.
Figure 3 sampling resistance Rset determines the constant current drive circuit design, and has a significant impact on the efficiency of the entire system, so careful design the Rset to energy savings is critical. Figure detailed design documents 3 and 4 of the National Semiconductor please ask your local authorized distributors. n general, if the LED drive current changes require no more than 5-10% of the nominal value, then use the precision of 2% resistor is enough. A typical LED drive current fluctuation range of plus or minus 10%. Due to the large sampling resistor power consumption, avoid using smaller power chip resistors. In addition, LM3478 scheme suitable for multiple high-power LED constant current driver, and based on LM5021 constant current driver design is targeted at 220V AC / DC converter applications.Constant current driver and thermal considerations On electronic circuit design, the engineers in the design of LED constant current driver circuit must first understand the LED constant current parameters. At present a lot of LED chip manufacturer, the difference of LED at home and abroad mainly lies in the same electrical parameters, number of lumens may be different, so the design engineer must clearly recognize the power is not the only parameter for LED luminous efficiency. For example, the same 1W of LED, some LED can reach 40 lumens of brightness, while others can only achieve 20 lumens of brightness, this is because the LED optical efficiency also depends on the materials and the production process and many other aspects. Some designers through increase the driving current of led to improve the luminous efficiency.for example, the same 1W LED, the drive current is increased as before the brightness can be increased from 20 lumens to 40 lumens, but the LED working temperature also increased.. Once the temperature exceeds the limit LED temperature point, it will affect LED life and reliability, which is an important issue in the design process of constant current driver need to pay attention.In addition, the optical efficiency of LED lighting systems depends not only on LED constant current driver program, is also closely related to the thermal design of the whole system. To reduce the volume, some LED constant current drive system make the LED drive circuit and the heat dispose part close to the design, so it is easy to affect the reliability.In general, the heat source of LED lighting system form the LED the lamp itself, the heat source is too concentrated will produce heat loss, so the LED driving circuit and temperature dissipation system can not close together. Recommends the following measures: LED lamp heat dissipation by cooling of the aluminum plate;
the power device is evenly distributed; as far as possible to avoid the LED drive circuit and the heat radiating part close to the design; thermal impedance restrain package to a printed circuit board; improve the heat flow LED chip to reduce the thermal impedance.

Figure 3
Figure4

Industrialization demonstration of key technologies–High-power LED indoor lighting dimming systems At present, various countries are pushing for LED lamps to replace incandescent lamps and fluorescent lamp power supply for residential, commercial and industrial applications,. While SCR dimming and PWM dimming LED lighting are common dimming ways.From a technical point of view, the main problem is that the thyristor dimmer compatibility between the power supply and LED, that for different types and different countries triac dimmers, due to poor adaptability was the cause of out the lights flicker and other phenomena, especially high-power LED indoor lighting dimming, has become a new challenge to many research institutions or enterprises. PWM dimming does not produce any Chromathography migration, even in a wide range dimming, flicker does not occur, and can achieve high accuracy of dimming,can be realized the intelligent control for lighting which combined The PWM and the digital control technology. At home and abroad have begun to implement intelligent control for lighting, but the some place intelligence on LED indoor lighting control is simple and not perfect, most still is the traditional manual management style, resulting in a waste of energy and economic losses. Therefore, an urgent need for the auto-dimming applications. Currently, Philips of the Netherlands, Germany Osram and other international giants are actively involved in research and development with dimming function LED indoor lighting products.

First–Through this project research,to solve the key technical problems of poor compatibility with traditional LED dimming power supply and triac dimmers. the development of 30W-60W triac dimming LED downlight product, to achieve a controlled and mainstream market SCR dimmer fully compatible;develop adaptive intelligent dimming LED ceiling products to solve the problem of traditional lighting energy waste because they can not demand dimming caused.

Second–the research content:
1, Automatic dimming pattern recognition technology.
2, the dimmer study automatic detection technology.
3, based on mcu to adaptive intelligent controlled dimming technology.
4, digital PWM dimming research generated EMI problems.
5, a functional study of LED lighting design methods to establish accurate optical model for the second optical design by the imaging optics and the illumination optics, and by applying the theory of the intermediate vision to obtain optimal effective light efficiency of the lamp.
6, the overall lighting design research methods, the use of driving the inside of integrated design and realize ultra-thin thickness lamps, increase aesthetics and reduce costs.

For the bar operators, the importance of lighting design. Lighting can not only affect the person to create a variety of atmosphere, but also create an important element Colorful space. For bar decoration, the role of the lights just for lighting, create an atmosphere, to create a personalized innovative bar environment, We should consider to forsake one’s former than in a popular style. lighting design reativity and innovation, in order to better reflected bar personalized decoration and meet the needs of the times and the customer.
To meet the needs of customers and the market, the bar decoration design is closely combined with the local culture between bar, bar itself the cultural characteristics and bar design style theme. Personality characteristics are the main characteristics of today’s, is also an important element of the bar to attract customers. So creative lighting design is necessary to grasp the main features of the bar, flexible use of the relevant elements of the bar decoration design.Implementation of creative lighting from the lighting design on the whole. including lamps and assign appropriate and position of reasonable distribution, straight, level and direction of transmission, diffuse and arrangement of strength and glare, control method and program direction, speed, production and integration environment, the bar the installation specification, and convenient, easy to repair, reasonable cost, high safety, comply with the relevant standards, policies, regulations and other factors.

Stage lighting decoration design. The stage is first attracted of the bar the attention of regional customers, so the decorative is very important for the stage, Should follow about three aspects: First, it directly affects the color of the light bar atmosphere. different colors of Lights have different effects, so with the stage lighting design should pay attention to the tone. For example, mutual collocation of warm and cool colors to produce different colors of light, it is possible to push the whole atmosphere of the bar to the highest point, Second stage lighting to focus on lighting design.To make it easier to attract customers, We considers the lighting theory should follow the “three-point lighting.” The so-called three-point lighting, also known as area lighting, typically used for smaller range of scene lighting. If the scene is large, it can be split into several smaller areas lighting. Usually there are three lights can be, respectively, as the main light, auxiliary light and background light. The main light is used to illuminate the scene in the main objects and the surrounding area, the main object is to also play to the subject object projection function. Last is a dynamic lighting design. In order to better achieve the effect of stage lighting, fully driven by the passion of customers, decorative lighting can be used when dynamic lighting, so that the whole stage dynamic.The light colors can choose yellow, purple, blue. The blue light can be used as background, because blue represents wisdom, eternal, as the background light, can add a sense of mystery.For the above mentioned three-point lighting method commonly used in the field of animation and film, for the film to add color. So how to use these lighting theory in the bar decoration?

Lighting course points to note., here we talk about the use of bar lights should pay attention to what issues?The bar is open generally at night, bar lights are in a cold state during the time of day, if in this state to push bright lighting control directly, it may cause the bulb “popping” sound or The lights have fused, so the lights have a warm-up period, when in the cold state (before opening) when the light bulb, the only console fader pushed up a little (often said calender state), so that bulb has micro-light, let in a warm state, to heat evenly, a few minutes after the warm-up, pushed a little brighter, longer warm-up after a few minutes, before the light completely push light. This will not only be able to prevent lamp failure, but also extend the lamp life.

Lighting technology: the basic knowledge about LED lighting project:
in recent years, LED lighting project received strong government support, the construction of city lighting engineering as an important measure to improve and beautify the environment of the city. What is the LED lighting project? What required to do for the LED lighting engineering?What do we care about it?

Below, we will give you a brief introduction about the basics of LED lighting engineering. before introducing the basics of LED lighting project, let’s repeat LED lighting works.LED (Light Emitting Diode), light emitting diode, is a solid state semiconductor devices, which can be directly Electricity into light. LED’s heart is an semiconductor wafer, the wafer is attached to an LED on the bracket, one end is negative, the other end connected to the power supply is Positive, so that the whole chip is epoxy encapsulated. The semiconductor wafer is composed of two parts, a Points are P-type semiconductor,it inside the hole dominated the other end is an N-type semiconductor, here is mainly electronic. ButWhen connecting the two semiconductors, to form a “P-N junction” between them. When the current through the wire into the semiconductor wafer.
Electronics will be to P area, complex in area P electrons and holes, , then it will emit energy,This is the principle of the LED light. The wavelength of light that is the color of light, forming a PN junction is made ​​of a material determined.

1.LED digital city projects of energy saving and efficient lighting brightness.

Also known as LED tube, LED guardrail lamps, LED lights outline; this product is used to building body contour installation, KTV Door head or advertising signs,
and road and bridge parapet lighting project; reach colorful water, chasing, scan results;
if made ​​of LED screens (LED yard signs) can be a variety of dazzling animation and flowers, You can also play video; the text and map Case. LED digital tube classified by the effect can be divided into: monochromatic light colors (red, yellow, blue, green, white); colorful can be divided into: single-stage colorful gradual transition; really sixth, really eight, paragraph 12 , 16 segments, 32 segments, 48 segments and so on. According to the control method is divided into: internal and external control. Internal control: control the led with The IC chip in tube. Directly connected the power after flash variety of pattern.explained the concept simply of external control is simply the need for an external controller; controller system is divided into offline and online systems; online system refers to the control system attached to the computer (more for LED digital tube screen); offline system work is not required attached to a computer,Input control signal to drive LED after connected power. to pay attention to installed outside the control signal.usually for signal input from the male, female for signal output;
2.LED rainbow tube LED rainbow tube

Also known as LED lights, LED rope light; is one of the most commonly used product on lighting project, and the price is relatively cheap, is Customer favorite LED lighting products. Mainly applied to the cost is not high, the effect is not too gorgeous place;
can make build Floor Body or signs outline; iron word or shape of the sides; KTV cove ceilings or decoration. LED rainbow tube classification
LED rainbow tube classification

The second round, round three lines, flat line, party line, flat three lines, flat four lines, flat five lines, flat seven line etc.; there are red, yellow,Blue, green, white, red, blue, red, red yellow blue, red yellow blue green;including LED lights, LED flexible neon lamp,make the installation ,try not take out all led form the reel, then the entire pull to the building body is provided; because if too much force will lead to a lamp with a line break(causing the lamp with irreparable damage),
If there is no light in the middle, you can cut the unit that does not light with a razor blade, and then use the middle connector docking.
In addition,must be reminded that,in the use of wires to the attention of the negative and power;

The power consumption is not to large, the main line using a national standard 4 Square millimeter of the main line, the line transformer to lamp using 2.5 square millimeter wires. The signal line as far as possible the use of ultra five network.Transformers and controller measures pay attention to waterproof rain.
We discussed the LED lighting engineering products — LED decorative lamp series LED star light
A LED star light (LED light string), LED net light, LED waterfall lamp, LED stars.These LED decorative lamp lighting in general use of flowers or small landscape. For example, to do lighting effects to a tree, you can use multiple strings LED star light, star lights around LED in the branches, and through the controller flashing, became flashes colors

Several of car internal and external lighting LED driver solution

LED (Light Emitting Diode), light-emitting diode, is a solid-state semiconductor devices, which can be converted directly into electricity to light. In recent years, the applications continue to expand, from the portable device backlight traditional to large size LCD display / LCD TV backlighting, automotive and general lighting field. This article will be devoted to a variety of LED driver solutions, suitable for car light, This paper will be devoted to the various LED drive scheme suitable for automotive lighting applications, and discusses some typical applications. and discuss some typical applications.   LED offers many advantages for automotive lighting applications,LED applications is very wide in car field, but can be summarized as interior lighting and exterior lighting (see Figure 1).

but simply classified into internal and external lighting lighting . External lighting as the headlight, Obe Terua, interior lighting including internal convenient and comfortable lighting and instrument panel backlight.
A lot of factors to promote the application of automotive LED lighting. With headlamp for example, the use of LED as a light source has many advantages:
1.1 to design flexible or novel
LED physical size is very small, can be used to develop extremely compact, thin modules. Compared with halogen and xenon lights, multi-string LED module requires a smaller, simpler lens and a light-diffusing sheet hardware. And a plurality of LED light source is easier to guide,
greatly reduce the impact that project in engineering design.
1.2 light intensity and energy efficiency continues to improve有用LED light intensity is fast on the lift curve, showing every 18-24 months flux will double trend. LED light output has more than halogen lamps,
future LED optical performance will also be able to rival the xenon lamp.
1.3 high reliability and long life
As long as the car headlamp effective thermal management module to maintain a low junction temperature, and protect it from the switch is turned on / off, the impact of the pulse and the battery current spikes may occur during can’t affect. Expect them to continue to use in the whole life cycle of the car.
1.4 significant energy savings
Compared with other solutions, car headlamps use fuel / energy is much less. Use high efficiency intelligent power Technology / chip, rather than a number of external components required general IC, can be more energy efficient.Therefore, LED automotive lighting applications in increasing, and by many car manufacturers as a design selling point.
2 LED driver solutions compare
LED automotive lighting applications in a variety of different applications of LED current requirements also vary, so the need to combine specific application requirements, select the appropriate LED driver solution.
One of the main features LED driver solution is the steady flow in a variety of working conditions, regardless of the input conditions and forward voltage variations. Driver programs must comply with energy efficiency, form factor, cost and safety aspects of the application requirements. Meanwhile, the selected solutions must be easy to use and strong enough, to meet strict environmental application specific.The typical LED driver program in automotive applications including resistors, linear LED driver, LED driver and innovative lighting switch management LED driver. In general, according to the size of LED current in the application, in low current application of 20 to 200 mA, can using discrete components (i.e. resistance) or linear driving solutions; in the secondary current application of 200 to 500 mA, can choose linear or switch driver solutions; and in high current applications is greater than 500 mA， in general please selection switch drive solutions.
In fact, the resistance is the easiest, lowest cost ,LED current limiting solutions, but they are not “steady flow”, but the LED forward voltage variation and input supply voltage variation and lead to current changes, will be causing the LED brightness variation, simply LED maximum current limit. Although the low cost of such programs, but also the lowest energy efficiency, and the existence of LED thermal runaway screening costs and thermal runaway problem.CCR is a higher performance solution and it has more lower cost than the switch driver. suitable for LED lighting applications in current is less than 200 mA. CCR cheap and rugged, providing a constant brightness over a wide voltage range, CCR maximum operating voltage of 50 V, the battery can withstand load dump. CCR provides SOD123, SOT123 and DPAK different packages to work (125 ℃)
This solution can reduce or eliminate the generation LED filter stock, so that a lower total cost of the program. CCR maximum operating voltage of 50 V, CCR provides SOD123, SOT123 and DPAK in different packaging, can work under strict thermal environment (125 ℃), In addition, CCR does not generate electromagnetic interference, easy to design.

Lighting and video equipment is the necessary equipment for modern dance hall, although it is in a subordinate position, but indispensable. You can create a variety of environments with light, create a different atmosphere, with pictures to show the rich connotations of music, make music more attractive, more appealing.

The DMX 512 protocol is the Digital Multiplex abbreviation, is the Grand Theatre, song and dance hall general signal control protocol, and also is an international agreement.USITT DMX512/1990 is light and the lighting console data transmission standard, is commonly used in the field of entertainment lighting control protocol. The previous 0-10V analog control by more, now DMX512 is a control protocol for entertainment lighting industry is the most important. USITT DMX512/1990 is put forward by the American Association of theater technology USITT. The original version was published in 1986, was amended in 1990.in 1990 as a standardized product, widely used in light control devices of entertainment place. This light control dimming produced only communication signals, does not provide all types of lamps (including computer power supply) power supply, controlled lighting requires that they have their own power supply.

At present, this signal standard has been widely recognized around the world theater and club industry, which is not only used for light dimming adjustment , also widely used in intelligent computer lights, power boxes and smoke control.
1 Set
DMX settings include three steps, the DMX is connected with the controlled device, set the DMX address (some system is not necessary), the end of DMX signal. To achieve these three steps in a sequence. Before access to power, must ensure that these steps are completed, or easily damage integrated module of DMX.

2, DMX system components

DMX system includes a controller (transmitter), lighting equipment (receiver) and cable. Use high-quality cable and plug according to figure 1 connect them.

DMX system includes a controller (transmitter), lighting equipment (receiver) and cable. Figure 1

Connect cable must be used for high-quality cable, due to the transmission stream is high-speed, low-quality cables will cause signal distortion, the system shut down or performing terminated.
Cables and power line can not be tied together, in order to avoid interfere with the signal.
3-pin XLR connector or 5-pin XLR is common in connection the same connection between the role of the tip, 1, grounded, 2, received signal is negative, 3, received signal positive. 4-5, end 5-pin XLR’s generally do not.

The address of intelligent light emitting device or computer equipped is required in the dmx system. the correct address is a key part of computer lamp operating properly, the wrong address can be cause it is not controlled by the optical control and error action or no response.
NOTE:more about dmx Informat please review web sit:
dmx-controller-led-controller

Definition:
Flexible Led strip refers to the strip of LED set mounted on FPC (flexible printed circuit board) (Attachment: Rigid Strip with PCB hard board), with SMD package high-brightness LED as light source, every three lights as a unit, will LED chip welding on the soft circuit board.
Components:
SMD flexible light strip waterproof divided into four :
Epoxy, waterproof casing, solid waterproof (U-groove + resin), filling plastic waterproof (casing + resin) Which conventional PU polyurethane with a high temperature resistance (tested in 40 ℃ -. -20 ℃, UV, folding, wear and other features)

Waterproof:
Not waterproof – bare board –IP00,
IP65 Epoxy waterproof,
IP67 silicone casing waterproof,
IP68-PVC tube filled waterproof (waterproof casing + Glue / half sleeve + Epoxy).Note: Epoxy glue is AB glue, the ratio was 1: 1,
casing material is silica gel (softness is good, for a long time will not yellowing, are not compatible with AB glue),
PVC (transparent, combination with AB glue, a long time will yellowing). Low pressure is to add a switching power supply, is a step-down rectification.
LED bead colors: red wavelength:620-625nm (nm)
yellow wavelength of 590~595nm
blue wavelength 475~480nm
green wavelength 520~525nm is cast beyond the above,
beyond the wavelength range is partial color,
white is usually defined by color temperature,
divided into: warm white color temperature 2700K-4000K (Kelvin) is white temperature 4000K-5000K cool white color temperature above 6000K.Divided into monochrome (white –5000K above,
warm white –2700K above, red, yellow, blue, green, pink, purple),
which is white, warm white, mostly blue followed.
There is a colorful (RGB) with the Symphony of the (plate than the IC,, there is flowing water effect, with digital effects like).
3.2.3, the brightness of brightness lamp beads with flux (lumens) lumen (LM) is defined, the higher the value, the higher the lumens brightness. There are several on the market now: 3528 (3-4LM, 4-5LM, 5-6LM, 7LM above) the first two are generally used for soft light strip, which is used for lamps, panel lights; 5050 (10 12LM, 12-15LM, 16-18LM) all of these can be used for flexible light strip, generally jewelry cabinet light bar that is hard for high brightness light bar is generally used 16-18LM’s.

Lamp specifications:
0603, 0805, 1210, 3528, 5050 refers to the LED size. size unit (inch / Metric), below are the details of these specifications: 0603: conversion to metric is 1005, which represents the length of LED components is 1.0mm, the width is 0.5mm. Industry referred to 1005, British, it is called 0603.
0805: conversion to metric is 2125, which represents the length of LED components is 2.0mm, the width is 1.25mm industry referred to 2125, British, it is called 0805.
1210: conversion to metric is 3528, that is represents the length of LED elements is 3.5mm, width is 2.8mm. Industry referred to 3528, British, it is called 1210.
3528: This metric is called, means that the length of the LED elements is 3.5mm, the width is 2.8mm, the industry referred 3528.
5050: This is also called the metric that indicates the length of the LED elements are 5.0mm, width is 5.0mm, the industry referred to as 5050. Most manufacturers of SMD lights are used mostly in 3528 and 5050,

Currently, the development of key LED strip technology is the base material and wafer growth techniques. Sapphire substrate material in addition to traditional materials, silicon (Si), silicon carbide other than the (SiC), zinc oxide (ZnO), and gallium nitride (GaN), etc. are also the focus of current research. improving the efficiency of the LED chip LED lighting has become the key to enhance the overall technical indicators. In just a few years, with the chip structure, surface roughening, improving the design of multi-quantum well structure and a series of technology, LED luminous efficiency of major breakthroughs in the develo pment of LED chip structure shown in Figure 1. LED quantum efficiency will be further improved, the luminous efficiency of LED chips will also rise.

(Figure 1)　The development course of LED chip structure
Thin film chip technology (Thinfilm) is the key technology to produce ultra-bright LED chips, can reduce the light loss, 97% of the light output from the front through the bottom of the reflecting surface
not only greatly improve the luminous efficiency of LED, also simple lens design.

Three packaging technology introduction

High-power LED packaging technology can be divided into a single chip, multi-chip integration and chip-board package three categories , the following will be described:

Luminous efficiency, heat dissipation and reliability advantages for single chip package Single-chip packaging technology package is the most widely used,its main technical bottleneck is the coating technology and fluorescent powder yield rate, chip color temperature,. Advantages of single-chip package is the high light efficiency, easy to disperse heat, easy to light distribution and reliability.Package shape and internal structure of SemiconductorsMulti chip integrated package for small volume can reach high luminous flux Multi-chip integrated high-power LED module assembly is currently the most common form of another package, can be divided into low-power and high-power chip integration of components into two categories,the former with six low-power chip integration of a 1watt high-power LED components，such integration led cod  has the advantage of low cost is the main way to make a lot of high-power LED assembly.(Figure 2)   by optimizing the design, the thermal resistance of the final product can be controlled 3.1 ℃ per watt, and can drive up to 15 watts of high power. The advantage of this package is to achieve a high flux in a very small space.

(Figure 2)

COB effectively improve defects — dissipation heat

COB technology follows the traditional semiconductor technology, which directly to the LED chip is fixed on the printed circuit board (PCB). Using this technique, there are only 0.3 mm thickness of less than LED.Because the LED chip in direct press close to the PCB board,increasing the area of heat conduction and heat dissipation problems can be improved. This package to form more small power chip. This package mostly low-power-led-chip